Key Food Furanones Furaneol and Sotolone Specifically Activate Distinct Odorant Receptors.

Franziska Haag,Sandra Hoffmann,Dietmar Krautwurst

doi:10.1021/acs.jafc.1c03314

Franziska Haag, Sandra Hoffmann + Show 1 more

Open Access

https://doi.org/10.1021/acs.jafc.1c03314

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Abstract

Furanones formed during the Maillard reaction often are natural aroma-determining compounds found in numerous foods. Prominent economically relevant representatives are the structural homologues Furaneol and sotolone, which are important natural flavoring compounds because of their distinct caramel- and seasoning-like odor qualities. These, however, cannot be predicted by the odorants' molecular shape, rather their receptors' activation parameters help to decipher the encoding of odor quality. Here, the distinct odor qualities of Furaneol and sotolone suggested an activation of at least two out of our ca. 400 different odorant receptor types, which are the molecular biosensors of our chemical sense of olfaction. While an odorant receptor has been identified for sotolone, a receptor specific for Furaneol has been elusive. Using a bidirectional screening approach employing 616 receptor variants and 187 key food odorants in a HEK-293 cell-based luminescence assay, we newly identified OR5M3 as a receptor specifically activated by Furaneol and homofuraneol.

Highlights

Furaneol (4-hydroxy-2,5-dimethyl-3(2H)-furanone) is probably one of the most important aroma compounds for the food industry
■ RESULTS AND DISCUSSION OR5M3 and OR8D1 Exclusively Responded to Furaneol and Sotolone, Respectively
We screened both compounds at 1000 μmol/L each, against 616 human odorant receptors (ORs) variants (Figure 1). Both Furaneol and sotolone each exclusively activated a single OR over a 2σ threshold (Figure 1). These are OR5M3 for Furaneol (Figure 1A) and OR8D1 for sotolone (Figure 1B)

Summary

Introduction

Furaneol (4-hydroxy-2,5-dimethyl-3(2H)-furanone) is probably one of the most important aroma compounds for the food industry. We set out to identify the best responding OR for Furaneol and sotolone and to characterize the identified receptors in a bidirectional screening approach, employing our KFO and IL-6-HaloTag-OR libraries in a HEK-293 cell-based luminescence assay, equipped with GloSensor technology.[2,18,19]

Results

Conclusion